Amid intense efforts by the Obama administration to target the uninsured in the U.S. president’s final months in the White House, sign-ups for health plans created under his signature domestic law are expected to rise by about 1 million next year.

The forecast illustrates the administration’s confidence in enrolling more people and keeping those who are covered from dropping out in a challenging year. But the Obamacare exchanges are still not attracting enough young, healthy and higher-income individuals who could help spread the health-care costs of the sickest over a bigger group.

“What we are still missing is the young and invincible,” said Deep Banerjee, an analyst at S&P Global Ratings. “The exchange market has to grow a lot more to become stable.”

About 13.8 million people will pick Affordable Care Act plans during the enrollment period that starts Nov. 1, the government estimated Wednesday, up from 12.7 million a year earlier.

The forecast is more optimistic than that of S&P Global Ratings, whose estimate is 11.7 million to 13.3 million.

“This is the last open enrollment for this administration,” Health & Human Services Secretary Sylvia Mathews Burwell said in a speech in Washington. “We’re going to make it count.”

2017 could be a particularly tough year to persuade people to sign up, with premiums rising and options narrowing in some markets. Surveys have shown that high costs are a key reason people aren’t buying plans, even when subsidies help lower premiums to under $100 a month for many individuals.

Passed in 2010, the ACA, among President Barack Obama’s key domestic policy achievements, helped push the number of people without insurance to record lows in the U.S. Still, millions of uninsured haven’t signed up and the law remains politically divisive. In the presidential race, Democratic candidate Hillary Clinton has called for bolstering subsidies to help more people buy coverage. Donald Trump, her Republican opponent, has said he’d repeal Obamacare while working to ensure that people were still able to find health insurance.

The government estimates that a third of the 10.7 million eligible uninsured will pick ACA plans for next year, underscoring the difficulty of reaching those who’ve been left behind by the law’s gains. Some people aren’t buying ACA plans because of their cost, according to a Commonwealth Fund study. A separate report from the Kaiser Family Foundation found that about 5.3 million of the 27.2 million who are uninsured may be eligible for financial subsidies to help them buy ACA coverage.

Outreach Strategy

The U.S. has said its outreach strategy for this year will emphasize the subsides that can help people buy health plans. About 84 percent of the uninsured who are eligible to buy plans have income levels that could qualify them for financial help, HHS said.

Subsidies are encouraging the uninsured to enroll, according to Lance Wilkes, an analyst at Sanford C. Bernstein & Co. Yet for people who aren’t eligible, the options remain too expensive, he said.

“The intent was to have a much larger public exchange market,” Wilkes said. “The overall price tag is too high for non-subsidized people.”

Average enrollment over the course of 2017 will be about 11.4 million people, up from 10.5 million in 2016, the U.S. said. Some people who select plans typically don’t pay their premiums, or drop their coverage over the course of the year, so those figures are lower than the number who pick plans.

The exchange enrollment figures don’t include individuals who’ve gained access to Medicaid through the ACA’s expansion of eligibility for the government health program for the poor. Also excluded are about 650,000 people enrolled in basic health programs in New York and Minnesota.

In her speech Wednesday, Burwell highlighted some of the ways the health law has changed the lives of Americans who didn’t have insurance before. Insurers can no longer exclude people with pre-existing health conditions from buying plans, opening up the markets to sick people. And plans can no longer have annual or lifetime limits on the amount they’ll spend on care.

“It’s easy to forget where the health insurance market was before the Affordable Care Act,” Burwell said, criticizing efforts to repeal the health law. “We can’t look backwards in a hopeless search for alternatives that aren’t viable, or just don’t exist.”